1         public static bool FindNumsWithSum(int[] arr, int sum, ref int numA, ref int numB)
 2         {
 3             if (arr == null || arr.Length < 1)
 4                 return false;
 5
 6             int start = 0;
 7             int end = arr.Length - 1;
 8             int temp = 0;
 9
10             while (arr[start] + arr[end] != sum && start < end)
11             {
12                 temp = arr[start] + arr[end];
13
14                 if (temp > sum)
15                     end--;
16                 else
17                     start++;
18             }
19
20             if (start == end)
21                 return false;
22             else
23             {
24                 numA = arr[start];
25                 numB = arr[end];
26             }
27
28             return true;
29         }

 1         public static void FindContinuousSequence(int sum)
 2         {
 3             int start = 1;
 4             int end = 2;
 5             int curSum = start + end;
 6
 7             while (start < (sum + 1) / 2)
 8             {
 9                 if (curSum < sum)
10                 {
11                     end++;
12                     curSum += end;
13                 }
14                 else if (curSum > sum)
15                 {
16                     curSum -= start;
17                     start++;
18                 }
19                 else
20                 {
21                     for (int i = start; i <= end; i++)
22                     {
23                         Console.Write(i);
24                     }
25                     Console.WriteLine();
26
27                     curSum -= start;
28                     start++;
29                 }
30             }
31         }